学术论文

      预测平房仓中小麦密度分布与储藏质量的模型

      Model of Density Distribution and Storage Quality of Wheat in a Horziontal Warehouse

      摘要:
      采用LHT-1粮食回弹模量仪测定小麦堆在不同压应力下的压缩密度,结果表明:当小麦[众麦1号,含水率为11.70%~18.18%(w“.)]的竖直压应力增大(0.631 ~221.060 kPa)压缩密度增大(740.50~853.85 kg/m3),两者可拟合出关系方程.建立平房仓中小麦的密度、应力与粮层深度关系的微分方程组,用数值方法计算平房仓中小麦密度与粮层深度关系,由积分法计算出平房仓中小麦的储藏质量.模型计算结果表明:平房仓中小麦密度随着粮层深度的增加而增大,随着深度增加,密度增加率减小;在一个宽20 m,长40 m的平房仓中,小麦密度从表层的800 kg/m3增加到10 m深处的833.5 kg/m3,密度增加了4.1%.在同一深处,密度随平房仓长、宽的尺寸增大而增大,增大值很小.在平房仓中同一深处,密度随含水率的增大而增大,增大值很小.小麦的摩擦角、小麦与仓壁摩擦系数几乎不影响平房仓中的密度.本模型计算了5个实仓中的小麦储藏质量,计算值与粮重实际账面数几乎一致,最大误差为2.63%.
      Abstract:
      The LHT-1 grain rebound modulus tester was used to determine the compression density of wheat heap under different pressure stresses.The results of experiment showed that as the vertical pressure stress of wheat [Zhongmai No.1,moisture content:11.70%~ 18.18% (w.b.)] increased from 0.631 ~ 221.060 kPa,the compression density of wheat increased from 740.50 ~ 853.85 kg/m3.The above two could be fitted out a relation equation.A differential equation group of relationship of wheat density,pressure and grain layer depth in a horizontal warehouse was derived.The results of calculation of this model showed that density of wheat in a horizontal warehouse increased along with the wheat depth,and rate of increase of density of wheat decreased along with the depth.In a 20 meter wide,40 meter long horizontal warehouse,as depth of wheat increased from 0 ~l0 m,density of wheat decreased from 800 ~ 833.5 kg/m3,density increased by 4.1%.At the same depth,the density increased along with size increase of the length and the width of the horizontal warehouse,and the increase value was very small.At the same depth,the density increased along with the increase of moisture,and the increase value was small.The friction angle of wheat and the friction coefficient of the wheat and wall almost had no influence on the density of wheat in the horizontal warehouse.This model calculated the storage weight of wheat in 5 horizontal warehouse,and the calculated value was almost the same as the actual book number of weight of wheat,and the maximum error was 2.63 %.
      Author: Cheng Xuduo Gao Mengyao Feng Jiachang Du Xiaocui
      作者单位: 南京财经大学食品科学与工程学院;江苏省现代粮食流通与安全协同创新中心,南京210046
      刊 名: 中国粮油学报 ISTICPKU
      年,卷(期): 2017, 32(3)
      分类号: TU261
      在线出版日期: 2017年4月18日
      基金项目: 国家自然科学基金,公益性行业(粮食)科研专项,江苏高校优势学科建设工程资助(苏政办